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<div class="titlepage"><div><div><h4 class="title">
<a name="asio.reference.thread_pool.notify_fork"></a><a class="link" href="notify_fork.html" title="thread_pool::notify_fork">thread_pool::notify_fork</a>
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<p>
          <span class="emphasis"><em>Inherited from execution_context.</em></span>
        </p>
<p>
          <a class="indexterm" name="asio.indexterm.thread_pool.notify_fork"></a> 
Notify the
          <a class="link" href="../execution_context.html" title="execution_context"><code class="computeroutput">execution_context</code></a>
          of a fork-related event.
        </p>
<pre class="programlisting">void notify_fork(
    fork_event event);
</pre>
<p>
          This function is used to inform the <a class="link" href="../execution_context.html" title="execution_context"><code class="computeroutput">execution_context</code></a>
          that the process is about to fork, or has just forked. This allows the
          <a class="link" href="../execution_context.html" title="execution_context"><code class="computeroutput">execution_context</code></a>,
          and the services it contains, to perform any necessary housekeeping to
          ensure correct operation following a fork.
        </p>
<p>
          This function must not be called while any other <a class="link" href="../execution_context.html" title="execution_context"><code class="computeroutput">execution_context</code></a>
          function, or any function associated with the execution_context's derived
          class, is being called in another thread. It is, however, safe to call
          this function from within a completion handler, provided no other thread
          is accessing the <a class="link" href="../execution_context.html" title="execution_context"><code class="computeroutput">execution_context</code></a>
          or its derived class.
        </p>
<h6>
<a name="asio.reference.thread_pool.notify_fork.h0"></a>
          <span><a name="asio.reference.thread_pool.notify_fork.parameters"></a></span><a class="link" href="notify_fork.html#asio.reference.thread_pool.notify_fork.parameters">Parameters</a>
        </h6>
<div class="variablelist">
<p class="title"><b></b></p>
<dl>
<dt><span class="term">event</span></dt>
<dd><p>
                A fork-related event.
              </p></dd>
</dl>
</div>
<h6>
<a name="asio.reference.thread_pool.notify_fork.h1"></a>
          <span><a name="asio.reference.thread_pool.notify_fork.exceptions"></a></span><a class="link" href="notify_fork.html#asio.reference.thread_pool.notify_fork.exceptions">Exceptions</a>
        </h6>
<div class="variablelist">
<p class="title"><b></b></p>
<dl>
<dt><span class="term">asio::system_error</span></dt>
<dd><p>
                Thrown on failure. If the notification fails the <a class="link" href="../execution_context.html" title="execution_context"><code class="computeroutput">execution_context</code></a>
                object should no longer be used and should be destroyed.
              </p></dd>
</dl>
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<h6>
<a name="asio.reference.thread_pool.notify_fork.h2"></a>
          <span><a name="asio.reference.thread_pool.notify_fork.example"></a></span><a class="link" href="notify_fork.html#asio.reference.thread_pool.notify_fork.example">Example</a>
        </h6>
<p>
          The following code illustrates how to incorporate the <code class="computeroutput">notify_fork()</code>
          function:
        </p>
<pre class="programlisting">my_execution_context.notify_fork(execution_context::fork_prepare);
if (fork() == 0)
{
  // This is the child process.
  my_execution_context.notify_fork(execution_context::fork_child);
}
else
{
  // This is the parent process.
  my_execution_context.notify_fork(execution_context::fork_parent);
}
</pre>
<h6>
<a name="asio.reference.thread_pool.notify_fork.h3"></a>
          <span><a name="asio.reference.thread_pool.notify_fork.remarks"></a></span><a class="link" href="notify_fork.html#asio.reference.thread_pool.notify_fork.remarks">Remarks</a>
        </h6>
<p>
          For each service object <code class="computeroutput">svc</code> in the <a class="link" href="../execution_context.html" title="execution_context"><code class="computeroutput">execution_context</code></a>
          set, performs <code class="computeroutput">svc-&gt;notify_fork();</code>. When processing the
          fork_prepare event, services are visited in reverse order of the beginning
          of service object lifetime. Otherwise, services are visited in order of
          the beginning of service object lifetime.
        </p>
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<td align="right"><div class="copyright-footer">Copyright &#169; 2003-2018 Christopher M. Kohlhoff<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
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